The present invention relates to seals, and particularly to a seal for a pipe extending through a wall.
Buildings and other structures are supported by a variety of services, such as water, gas, electric, and sewer. Conventionally, these services are distributed throughout the building by pipes. As hollow cylinders used to conduct a liquid, gas, wiring and the like, these pipes or conduits penetrate the floors, ceilings, and walls of most buildings.
Wherever a pipe penetrates the floor, ceiling, or wall (collectively, wall), it is desirable to install a seal assembly within a gap between the pipe and the wall. Here, gap seal assemblies allow longitudinal and radial movement of a pipe located in a partition wall. This is important during installation of the pipe. For example, when a pipe thermally expands or contracts, it is important that the seal is not dislodged from the wall.
After installation, gap seal assemblies also serve as fire stops. When fire develops in one room of a building, the fire will spread to adjoining rooms through any open orifice or gap. Thus, conventional gap seal assemblies employ fire resistant caulk to fill the gap between the wall and the pipe. However, there are numerous disadvantages to using caulk.
Caulk may take up to twelve days to cure and, correspondingly, twelve days to meet building fire codes. The thickness of caulk may vary and air bubbles may become trapped in it, affecting the fire rating. Caulk is not waterproof, cannot be installed in cold weather, and is messy when installed in ordinary and hot weather. Moreover, a worker must install caulk from both sides of the wall, which increases the number of work hours needed to complete a pipe installation job. Further, it is difficult to control the amount of caulk applied for each seal assembly, thus setting up a construction job that inevitably will result in waste. In addition, caulk hardens over time and becomes dislodged due to vibration.
In light of the above noted problems, the present invention works towards providing a multi-link seal assembly having material that swells when exposed to fire to create a fire stop seal. This eliminates many of the problems associated with the use of caulk. Moreover, since the seal assembly need not be tightened to the degree of conventional seals to create a fire stop seal, its installation time is reduced.
In a preferred embodiment, the multi-link seal assembly includes a plurality of seal blocks and a plurality of plates. The plurality of plates are integrally connected to the seal blocks to form a seal belt. The seal belt may be placed around a pipe and installed into a gap between a wall and a pipe. Each seal block is made of a material consisting of 2.4 weight percent expandable graphite, 6.6 weight percent brominated diphenyl oxide, 2.0 weight percent antimony trioxide, 16.8 weight percent carbon black, and other material to bring the total weight percent to 100 weight percent. Each seal block is configured to expand when a temperature adjacent to each seal block reaches 300 degrees Celsius. Moreover, each seal block is configured to form a hard, crust-like barrier when exposed to fire.
These and other features and advantages of the present invention will become apparent upon a reading of the detailed description and a review of the accompanying drawings. Specific embodiments of the present invention are described herein. The present invention is not intended to be limited to only these embodiments. Changes and modifications can be made to the described embodiments and yet fall within the scope of the present invention.